What Happens When You Get Peckish in Space?

Two astronauts explain how snacking works in orbit.

This post is part of Nosh, a special pop-up blog about snacks. Read more here.

It’s relatively common knowledge at this point that space ice cream—the freeze-dried kind that remains a staple in museum gift shops and comes in a crumbly, tri-colored block—is a bit of a misnomer. Every so often, an article appears with a headline along the lines of “Everything You Know About Space Ice Cream Is Wrong,” and Vox thoroughly debunked the myth in a 2016 interview with the last remaining member of the Apollo 7 mission—the only mission that was rumored to harbor the chalky confection. “We never had that stuff,” lunar module pilot Walt Cunningham said, taking the shine off of fond childhood memories with the rough cloth of reality.

When you think about the low-gravity environment of space, it makes sense that a snack like freeze-dried ice cream never made it off the ground. According to former Commander of the International Space Station Chris Hadfield, crumbly food is generally considered hazardous in space. “Anything that has crumbs doesn’t work without gravity,” Hadfield told me. “The crumbs will float all over and get in your eyes and you’ll breathe them—it’s just super messy.” So Nature Valley granola bars are effectively ruled out, as would be lots of other munchies we Earthlings enjoy. But does that mean astro food needs to be, as the Atlantic’s Megan Garber once described it, just “different enough from the product it’s trying to emulate that it serves only as a sad reminder of what it is not?”

Not so, according to both Hadfield and former U.S. astronaut Clayton “Astro Clay” Anderson, who both described the food they ate during their combined 333 days in space as pretty tasty. But there are multiple factors beyond taste that NASA has to take into account when designing food for the great beyond.

Aside from a prejudice against crumbs, space food has to keep for a long time, meaning it must be stable enough to last the entire journey into space, which includes packaging, testing, transport, and eventual space travel. According to Hadfield, a year could easily pass between when the food is cooked to when it’s delivered to the station. While NASA scientists have moved beyond the tube-and-cube method of food delivery, snacks and meals still tend to be either dehydrated or thermostabilized, which according to NASA means that the food is “heat processed to destroy deleterious microorganisms and enzymes.” Most entrees, which currently include offerings like beef stroganoff with noodles, chicken à la king, and Mexican scrambled eggs, are packaged in flexible pouches, while snacks of fish or fruit are packaged in cans. Pouched food is cooked in a forced-air convection oven or rehydrated using hot or cold water and then eaten straight out of the pouch.

One of the unfortunate side effects of microgravity on the human body, besides semiconstant nausea, is a decreased sense of taste. Without gravity to pull all the fluid in your body in the right direction, your sinuses end up constantly clogged, so six months in space is pretty similar to having a six-month-long head cold. “Your sinuses are pounding and you can’t really taste your food. It’s like that the whole time,” Hadfield said. This explains why Sriracha sauce and mustard are popular condiments, and why one of the most popular extraterrestrial bites is a freeze-dried shrimp cocktail.

That’s right: Since 1965, astronauts have declared cooked shrimp, tails and heads removed, swimming in tomato sauce and horseradish, one of the best space foods around. Shuttle astronaut Bill Gregory ate a legendary 48 meals straight with a side of shrimp cocktail, and both Hadfield and Anderson mentioned the classic hors d’oeuvre as a favorite. While Anderson just described himself as a “big horseradish guy,” Hadfield explained that the popularity of the snack can be explained by two factors: Shrimp rehydrates surprisingly well, and horseradish is both a strong flavor and a pretty effective decongestant.

The good news is, reconstituted shrimp cocktail aside, space snacking can be pretty similar to Earth snacking. Before Anderson began his 2007 tour of duty on the ISS, he and his family were even allowed to pick out space-suitable tidbits like Girl Scout cookies, Oreo snack packs, and Tootsie Roll Pops. “My wife sent some caramel popcorn from the Boy Scouts, which was allowed to come up, but man, as soon as I opened that it was a disaster,” Anderson laughed. “There was popcorn everywhere. It still tasted really good.” Hadfield’s favorite stellar snacks included Tim Horton’s coffee, chocolate, and strangely enough, a fruitcake that was sent to the astronauts by Trappist monks stationed in the Ozarks.

He even had real ice cream. Because astronauts’ blood and urine are analyzed by teams on the ground, when resupply vehicles are sent up to the ISS they’re sometimes loaded with a small active freezer to store the samples. Rather than send the freezer up empty, real ice cream will be sent up as a special treat. “NASA scientists were very concerned that we would somehow mix up frozen urine samples with Blue Bell ice cream,” Hadfield laughed. “I reassured them that we would be able to tell the two apart.”

Slate thanks Clayton “Astro Clay” Anderson and Chris Hadfield for their assistance with this post.

Anderson’s award-winning book The Ordinary Spaceman, “Astronaut Edition”Fisher Space Pen, and children’s books A Is for Astronaut; Blasting Through the Alphabet and It’s a Question of Space: An Ordinary Astronaut’s Answers to Sometimes Extraordinary Questions are available at www.AstroClay.com. Follow him @Astro_Clay.